Soldiers from the Indian army conducted an operation against militant groups along the border with Myanmar in the country’s northeast on Tuesday, with special forces allegedly also entering Myanmar to perform “surgical strikes”.

A statement by the army said its offensive had resulted in “significant casualties” among the militants who killed 20 Indian soldiers in the region less than a week ago, Reuters reported.

Carrying out cross-border operations is not common practice for India, and the army only mentioned two areas in its own states Nagaland and Manipur. However, Rajyavardhan Singh Rathore, Minister of State for Information and Broadcasting and a former army colonel, confirmed that Indian forces had crossed over into Myanmar, the Indian Express reported.

Maj. Gen. Ranbir Singh, the Additional Director General for Military Operations, told the Express that the Indians had been in communication with Myanmar authorities regarding the counteraction against the rebel groups.